1. Field of the Invention
This invention relates to poured concrete building deck structures which may perform the function of floors or roof decks on steel frame buildings. The concrete for the deck structure is poured over a corrugated sheet metal form deck which is supported by steel frame girder and spandrel members. The edge of the deck may extend beyond the girder which is closest to the building line or a designated line of an opening inside the building. The improved building deck described in our related application provides strength to the metal form deck at the sides which are normally parallel to the corrugations of the metal form deck and provides an adjustable edge bracket around four sides of the deck structure for easy and precise alignment with the desired building line. If the edge extends a substantial distance from the nearest structural girder, however, scaffolds or other sub-deck assembly supports may be required to support the edge construction during and after alignment. This invention relates to improved edge constructions which do not require sub-deck supports and may be easily and safely aligned with the building line or designated line.
2. Description of the Prior Art
In present day steel frame building construction, particularly of multi-story residential, office and industrial buildings, the floor and roof decks may be constructed by laying a deeply corrugated metal form deck over the horizontal steel frame girder and spandrel members and surrounding the edges of the deck with a vertical edge form. Concrete is poured on top of the metal form deck, usually with reinforcing bars or mesh embedded therein to provide structural strength. The concrete construction loads are restrained by the edge form.
Modern building designs often specify that the edge of the deck must extend beyond the girders and columns which are adjacent the building line or a designated line of an opening inside the building. Taller buildings generally have larger columns, and extend further from the edge girders and columns. Several problems may be encountered in the construction of such decks. One problem is that if the corrugated metal form deck extends over and beyond the horizontal girder members, the edges of the deck parallel to the corrugations of the metal create a dangerous working situation and require expensive sub-deck structural bracing to support the edge construction of the metal form deck. The same problem exists at openings in the floor and roof decks in the interior of the building, such as elevator shafts, stairways, atriums and the like.
Another problem which arises along the sides of the building parallel to the corrugations in the corrugated metal form deck is alignment of the edge of the deck with the desired building line, which cannot usually be measured from the girders beneath the deck since the girders are frequently not in the desired alignment. The same building line alignment problem exists at the sides of the building which are perpendicular to the corrugations of the metal form deck in that the ends of the metal pan must either be tediously aligned or cut with a torch to the exact building line requirement after proper dimensions are ascertained.
Attempts have been made to solve these problems by securing the deck structure to the girder which is closest to the building line or opening inside the building and using L-shaped pans secured to the edge girder to provide desired stiffness to the edge of the deck and to provide an edge form for the concrete, as seen in U.S. Pat. No. 3,024,573. However, it is difficult to install the L-shaped pans precisely to form the desired building line because they are not supported during alignment. Also, the pans must be properly aligned with the desired building line upon installation, and may not be installed and later aligned. Thus, if the building line has not been determined before installation, the installation crew will be delayed, which is expensive. Further, if the pans extend substantially beyond the edge girder, they must be installed from scaffolding from the floor beneath or supported by a sub-deck assembly. The weight of the concrete may be significant, requiring substantial support. The scaffolding and/or sub-deck supports are heavy and expensive, and at the edge of the building, create a particularly dangerous working condition. Also the expense incurred in merely transporting the scaffolding and/or sub-deck supports throughout the building during construction is substantial. These difficulties in construction are more acute as buildings are designed with more and more floors, as edges extend further and further from the nearest adjacent girder, and as the costs of construction increase.
Accordingly, an object of this invention is to provide a metal form deck structure having an edge construction which is supported from the top of the deck without the necessity of erection of scaffolding or other sub-deck support apparatus at the edge of the deck blow to complete the form deck structure.
Another object is to provide a metal form deck structure which is supported while it is aligned with the desired building line or opening.
Yet another object is to provide a metal form deck structure which has a modular edge construction that may be constructed at oblique angles to adjacent modules and to the girder to which the modules are secured.
Still another object is to provide a metal form deck structure which has reduced concrete at the edges of the structure and provides lateral stiffness along the modules of the edge construction.
It is another object of this invention to provide a poured concrete building deck structure having a protective and readily removable toe board around the edges and all openings, and to provide for easy installation and removal of a perimeter rail to protect workers during construction.
It is a still further object of this invention to provide a modular edge construction having pieces which may be easily stacked for storage and transportation.